This invention relates to the semi-conductor processing industry and particularly to an improved carrier for semi-conductor wafers. In some of the steps for fabricating semi-conductor devices, a batch of the wafers are placed in a cassette or carrier, usually referred to as a "boat", and a group of such boats are placed on an elongated sled or wheeled cart and moved into a furnace for various treatment, such as oxidation, diffusion, annealing and low pressure vapor deposition.
Each boat is provided with a plurality of slots for vertically supporting the wafers in spaced, parallel relation. This is important in that in order to have uniformity between the wafers resulting in a high yield of acceptable product, the gasses that are conducted through the furnace during the wafer processing operation, should preferably flow past each of the wafers in generally the same manner. However, the boats that have been heretofore employed have structure, such as transverse pickup tubes, located at the ends of the boats that enables them to be lifted by a tool and placed onto the cart from the side of the cart. This is a convenient way to position a series of boats on the cart; however, a major disadvantage of this approach is that it creates a wafer gap between the ends of adjacent boats and these gaps produce lack of uniformity of the gas flow past a series of boats filled with wafers, resulting in a low yield of acceptable product. In addition, the gaps represent lost space within the furnace in the sense that no wafers are being treated in the gaps. Accordingly, a need exists for an improved wafer boat that is constructed to eliminate the gaps in a convenient and practical manner.